Fuel cell subassemblies incorporating subgasketed thrifted membranes

ABSTRACT

A fuel cell roll good subassembly is described that includes a plurality of individual electrolyte membranes. One or more first subgaskets are attached to the individual electrolyte membranes. Each of the first subgaskets has at least one aperture and the first subgaskets are arranged so the center regions of the individual electrolyte membranes are exposed through the apertures of the first subgaskets. A second subgasket comprises a web having a plurality of apertures. The second subgasket web is attached to the one or more first subgaskets so the center regions of the individual electrolyte membranes are exposed through the apertures of the second subgasket web. The second subgasket web may have little or no adhesive on the subgasket surface facing the electrolyte membrane.

CROSS REFERENCE TO RELATED APPLICATION

This application claims the benefit of U.S. Provisional PatentApplication No. 61/289036, filed Dec. 22, 2009, the disclosure of whichis incorporated by reference herein in its entirety.

This Invention was made with U.S. Government support under Contract No.DE-FG36-07G017006 awarded by the Department of Energy. The Governmenthas certain rights in this invention.

FIELD OF THE INVENTION

The present invention relates generally to fuel cell subassemblies andsystems for fabrication of fuel cell subassemblies.

BACKGROUND

A fuel cell is an electrochemical device that combines hydrogen fuel andoxygen from the air to produce electricity, heat, and water. Fuel cellsdo not utilize combustion, and as such, fuel cells produce little if anyhazardous effluents. Fuel cells convert hydrogen fuel and oxygendirectly into electricity, and can be operated at much higherefficiencies than internal combustion electric generators, for example.

A typical fuel cell power system includes a power section in which oneor more stacks of fuel cells are provided. The efficacy of the fuel cellpower system depends in part on the integrity of the various contactingand sealing interfaces within individual fuel cells and between adjacentfuel cells of the stack.

A subgasket may be deployed on the electrolyte membrane of a fuel cellto seal the active regions of the fuel cell and to provide dimensionalstability to the electrolyte membrane. Under pressure, the edges of fuelcell components in the stack can cause local stress concentrations onthe membrane which may cause failure of the fuel cell. Subgasketsprovide support to the membranes to reduce the occurrence of thisfailure mechanism.

SUMMARY

Embodiments involve a fuel cell roll good subassembly having a pluralityof individual electrolyte membranes. One or more first subgaskets areattached to the individual electrolyte membranes. Each of the firstsubgaskets have at least one aperture and the first subgaskets arearranged so that first surfaces of the center regions of the individualelectrolyte membranes are exposed through the apertures of the firstsubgaskets. A second subgasket comprises a web having a plurality ofapertures. The second subgasket web is arranged so that second surfacesof the center regions of the individual electrolyte membranes areexposed through the apertures of the second subgasket web.

Other embodiments include a fuel cell roll good subassembly including asubgasket web having a plurality of apertures attached to a plurality ofindividual electrolyte membranes. The subgasket web is arranged so thatsurfaces of the center regions of the individual electrolyte membranesare exposed through the apertures of the subgasket web.

Some embodiments involve a fuel cell assembly including an electrolytemembrane having a first subgasket adhesively attached to the electrolytemembrane. The first subgasket has a first subgasket surface orientedtoward the electrolyte membrane and a first adhesive layer disposed onthe first subgasket surface. The fuel cell assembly includes a secondsubgasket, having a second subgasket surface oriented toward theelectrolyte membrane. The second subgasket does not include a secondadhesive layer on substantial portions of the second subgasket surface.

A fuel cell roll good subassembly includes a plurality of individualelectrolyte membranes, each individual electrolyte membrane having acenter region. One or more first subgaskets are adhesively attached tothe individual electrolyte membranes, each of the first subgasketshaving at least one aperture. The first subgaskets arranged so thecenter regions of the individual electrolyte membranes are exposedthrough the apertures of the first subgaskets. The fuel cell roll goodassembly also includes a second subgasket comprising a web having aplurality of apertures. The second subgasket web is arranged so thatsecond surfaces of the center regions of the individual electrolytemembranes are exposed through the apertures of the second subgasket web.An adhesive layer is not disposed on substantial portions of the secondsubgasket surface.

An automated roll to roll method of making a fuel cell roll goodsubassembly includes providing relative motion between an elongatedfirst subgasket web having a plurality of apertures and a plurality ofindividual electrolyte membrane. The individual electrolyte membranesare aligned with the first subgasket web so that a center region of eachelectrolyte membrane is aligned with an aperture of the first subgasketweb. The individual electrolyte membranes are attached to the firstsubgasket web.

According to one implementation, the first subgasket web may be cut intoa plurality of individual subgasketed membranes. A second subgasket webhaving a plurality of apertures is aligned with the plurality ofindividual subgasketed membranes so that a center region of eachelectrolyte membrane is aligned with an aperture of the second subgasketweb. The individual subgasketed membranes are attached to the secondsubgasket web.

According to another implementation, a second subgasket web having aplurality of apertures may be aligned and attached to the firstsubgasket web having the individual membranes attached thereto.

The above summary of the present invention is not intended to describeeach embodiment or every implementation of the present invention.Advantages and attainments, together with a more complete understandingof the invention, will become apparent and appreciated by referring tothe following detailed description and claims taken in conjunction withthe accompanying drawings.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 depicts a typical fuel cell and its basic operation;

FIGS. 2A, 2B, and 2C are plan and cross section views of a fuel cellsubassembly incorporating a thrifted electrolyte membrane and a onesided adhesive subgasket;

FIG. 2D is a cross section view of a five layer membrane electrodeassembly incorporating the subgasketed membrane of FIG. 2A and catalystcoated gas diffusion layers;

FIGS. 2E-2G illustrate various subgasketed electrolyte membrane whereinsubstantial portions of at least one subgasket layer have no adhesive;

FIG. 2H illustrates a subgasketed electrolyte membrane wherein a portionof at least one of the subgasket layers includes a surface treatmentthat reduces membrane movement;

FIG. 3A is a cross section of a thrifted catalyst coated membrane with aone sided adhesive subgasket;

FIG. 3B is a cross section view of a five layer MEA incorporating thesubgasketed catalyst coated membrane of FIG. 3A;

FIG. 3C illustrates an MEA incorporating a half subgasketed CCM;

FIG. 4 illustrates a fuel cell roll good comprising a fuel cellsubassembly web;

FIGS. 5A-5C are plan, y direction, and x direction cross sectional viewsof a fuel cell subassembly web comprising many concatenated fuel cellsubassemblies;

FIGS. 5D, 5E, and 5F are plan, y direction, and x direction crosssectional views, respectively, of a five layer MEA web incorporating thefuel cell subassembly web of FIG. 5A;

FIGS. 5G and 5H are plan and cross sectional views, respectively, of afuel cell subassembly web comprising many concatenated fuel cellsubassemblies having individual electrolyte membranes, and individualfirst subgaskets;

FIGS. 5I and 5J are plan and cross sectional views, respectively, of afive layer MEA web incorporating the fuel cell subassembly web of FIG.5G;

FIGS. 6A-6C illustrate a fuel cell subassembly web with CCM thrifting inx and y directions;

FIGS. 6D, 6E, and 6F illustrate a five layer MEA web that is formedusing the fuel cell subassembly web of FIG. 6A;

FIGS. 6G and 6H are plan and cross sectional views, respectively, of afuel cell subassembly web comprising many concatenated fuel cellsubassemblies having individual CCMs, and individual first subgaskets;

FIGS. 6I and 6J are plan and cross sectional views, respectively, of afive layer MEA web incorporating the fuel cell subassembly web of FIG.6G;

FIGS. 7A-7F illustrate fuel cell subassembly webs that include x and ydirection electrolyte membrane thrifting with subgaskets with adhesiveon both first and second subgasket layers;

FIGS. 7G and 7H are plan and cross sectional views, respectively, of afuel cell subassembly web comprising many concatenated fuel cellsubassemblies having individual electrolyte membranes, and individualfirst subgaskets;

FIGS. 7I and 7J are plan and cross sectional views, respectively, of afive layer MEA web incorporating the fuel cell subassembly web of FIG.7G;

FIGS. 8A-8F illustrate fuel cell subassembly webs that include x and ydirection CCM thrifting with subgaskets with adhesive on both first andsecond subgasket layers;

FIGS. 8G and 8H are plan and cross sectional views, respectively, of afuel cell subassembly web comprising many concatenated fuel cellsubassemblies having individual electrolyte membranes, and individualCCMs;

FIGS. 8I and 8J are plan and cross sectional views, respectively, of afive layer MEA web incorporating the fuel cell subassembly web of FIG.8G;

FIG. 9 is a process flow diagram illustrating a process for manufactureof subgasketed fuel cell subassembly webs;

FIGS. 10A-10D illustrate various subsystems of a roll-to-roll basedsystem configured to produce x and y thrifted fuel cell subassembliesincluding subgasketed membrane webs, individual subgasketed membranes,five layer MEA webs, individual five layer MEAs, and variousintermediate fuel cell subassemblies

FIGS. 11A-11N are x direction (down web) cross sections of input,intermediate, and/or output subassembly webs or subassemblies producesby the subsystems of FIGS. 10A-10D;

FIGS. 12A and 12B illustrate optional subsystems for pre-treatingelectrolyte membranes;

FIG. 13A is a cross sectional diagram of a foamed vacuum die roller;

FIG. 13B an embodiment of a foamed vacuum die roller and a process formaking a the foamed vacuum die roller;

FIG. 14 illustrates a sample MEA construction having a two sidedadhesive subgasket prior to temperature testing;

FIG. 15 illustrates the MEA construction of FIG. 15 after temperaturetesting;

FIG. 16 illustrates an MEA construction that incorporates a one-sidedadhesive subgasket on the membrane prior to temperature testing; and

FIG. 17 illustrates the MEA construction of FIG. 18 after temperaturetesting. While the invention is amenable to various modifications andalternative forms, specifics thereof have been shown by way of examplein the drawings and will be described in detail. It is to be understood,however, that the intention is not to limit the invention to theparticular embodiments described. On the contrary, the intention is tocover all modifications, equivalents, and alternatives falling withinthe scope of the invention as defined by the appended claims.

DETAILED DESCRIPTION OF VARIOUS EMBODIMENTS

In the following description of the illustrated embodiments, referenceis made to the accompanying drawings which form a part hereof, and inwhich is shown by way of illustration, various embodiments in which theinvention may be practiced. It is to be understood that the embodimentsmay be utilized and structural changes may be made without departingfrom the scope of the present invention.

The basic components of a fuel cell 110 (without subgaskets, gaskets, orseals) are depicted in FIG. 1. In operation, hydrogen fuel, H₂, isintroduced into the anode portion of the fuel cell 110, passing over thefirst fluid flow plate 112 and through the gas diffusion layer (GDL)114. On the surface of the catalyst layer 115, the hydrogen fuel isseparated into hydrogen ions (H⁺) and electrons (e⁻).

The electrolyte membrane 116 permits only the hydrogen ions or protonsand water to pass through the electrolyte membrane 116 to the cathodecatalyst layer 113 of the fuel cell 110. The electrons cannot passthrough the electrolyte membrane 116 and, instead, flow through anexternal electrical circuit in the form of electric current. Thiscurrent can power an electric load 117, such as an electric motor, orcan be directed to an energy storage device, such as a rechargeablebattery.

Oxygen, O₂, flows through the second flow field plate 119 and throughthe second GDL 118 at the cathode side of the fuel cell 110. On thesurface of the cathode catalyst layer 113, oxygen, protons, andelectrons combine to produce water (H₂O) and heat.

Individual fuel cells, such as the fuel cell 110 shown in FIG. 1, can becombined with a number of other fuel cells to form a fuel cell stack.The number of fuel cells within the stack determines the total voltageof the stack, and the surface area of each of the cells determines thetotal current. The total electrical power generated by a given fuel cellstack can be determined by multiplying the total stack voltage by totalcurrent.

A fuel cell stack is a sealed structure. Subgaskets, gaskets and/orseals are typically deployed around the perimeter of the active area ofthe electrolyte membrane. Catalyst may be disposed on the surfaces ofthe membrane, on the GDLs, or may be disposed partially on the GDLs andpartially on the membrane. The subgaskets and/or gaskets may be placedon, over, or about one or both surfaces of the electrolyte membrane,and/or on one or both surfaces of the GDLs, and/or on one or bothsurfaces of the fluid flow plates that face the GDLs.

Mass production of MEAs and/or fuel cell other subassemblies is neededto reduce the cost of fuel cell power generation to a point that willallow incorporation of this technology into wider use. In addition tomass production, reduction in the component costs also brings down theoverall cost of the final product. The electrolyte membrane is one ofthe more expensive components of an MEA and it is generally desirable todecrease the amount of electrolyte membrane used to form roll good fuelcell subassemblies, thereby decreasing the cost of the fuel cell stacks.Techniques for decreasing the amount of electrolyte membrane used in anMEA is referred to herein a “membrane thrifting.”

Some embodiments discussed herein illustrate membrane thrifted fuel cellsubassembly webs, as well as processes and systems for making thriftedfuel cell subassembly webs. Membrane thrifting involves manufacturingprocesses that conserve membrane material to lower the overall cost offuel cell subassembly roll good products, for example.

Some embodiments illustrate subgasketed fuel cell subassembliesincluding an electrolyte membrane or catalyst coated membrane (CCM)disposed between first and second half subgaskets. The first halfsubgasket has a first surface oriented toward the electrolyte membraneand the second half subgasket has a second surface oriented toward theelectrolyte membrane. At least one of the first and second half gasketsurfaces has an adhesive layer. Substantial portions of at least one ofthe first and second half gasket surfaces has no adhesive layer.“Substantial portions” of a subgasket surface having no adhesive layermeans at least 25% of the subgasket surface, or at least 50% of thesubgasket surface, or substantially all of the subgasket surface has noadhesive layer. In MEAs having a first half gasket with an adhesivelayer and second half gasket that is devoid of adhesive, the second halfgasket is adhesively attached to the first half subgasket via theadhesive layer of the first half subgasket and is not attached to themembrane by adhesive.

In some applications, a subgasket comprising a first half subgaskethaving adhesive on the surface facing the electrolyte membrane and asecond half subgasket having substantial portions or all of the surfacefacing the electrolyte membrane devoid of an adhesive layer improves thestability of subgasketed fuel cell subassemblies. For example, attemperatures exceeding 80 degrees C. and under pressure, the electrolytemembrane can be displaced relative to the subgasket by extrusion orshifting of the electrolyte membrane even though an adhesive layer ispresent on the surfaces of both subgasket layers. Without wishing to bebound by any specific theory for this phenomenon, one explanation isthat at higher temperatures the adhesive present at the interface of thesubgasket layers and membrane becomes slightly more lubricating,allowing the membrane to shift and/or extrude when pressure is applied.However, when a substantial portion of at least one subgasket surfacehas no adhesive present, shifting and/or extrusion of the membrane isdecreased even though a substantial portion of the other subgasketsurface includes adhesive. The decreased shifting and/or extrusion ofthe electrolyte membrane may be due to the increased friction betweenthe electrolyte membrane and the subgasket layer without adhesive.

FIG. 2A is a plan view and FIG. 2B and 2C are cross sectional viewstaken through lines A-A′ and B-B′, respectively, of fuel cellsubassembly 201. The subassembly 201 comprises an electrolyte membrane210 and a subgasket 220 comprising first and second half subgaskets 230,240. Half subgaskets 230, 240 are disposed at the perimeter of theelectrolyte membrane 210 and have the form of a “frame” having apertures233, 243 through which center portions of the electrolyte membrane 210are exposed. Although rectangular frame-shaped half subgaskets are shownin FIG. 2A, the half subgaskets may take on any shape, e.g., circular,pentagonal, hexagonal, etc. In addition, each half subgasket 230, 240may be one continuous layer, or may include several pieces that arearranged around the perimeter of the electrolyte membrane. Each of thehalf subgaskets 230, 240, may include one or more layers.

The first half subgasket 230 may the same size or a different size fromthe second half subgasket 240. If the first half subgasket and thesecond half subgasket are the same size, as depicted in FIGS. 2A-2C,then the edges 230 a, 230 b, 230 c, 230 d of the first half subgasket230 align with corresponding edges 240 a, 240 b, 240 c, 240 d of thesecond half subgasket 240. However if the first half subgasket and thesecond half subgasket are not the same size, then one or more edges ofthe first half subgasket do not align with the corresponding edges ofthe second half subgasket.

The first half subgasket aperture 233 may be the same size or adifferent size from the second half subgasket aperture 243. FIGS. 2A-2Cillustrate an implementation wherein the aperture 233 of the first halfsubgasket 230 is smaller than the aperture 243 of the second halfsubgasket 240. When the first half subgasket aperture 233 is smallerthan the second half subgasket aperture 243, then or more of the firsthalf subgasket aperture edges 233 a, 233 b, 233 c, 233 d do not alignwith corresponding ones of the second half subgasket aperture edges 243a, 243 b, 243 c, 243 d. In some configurations, the first half subgasketaperture is the same size as the second half subgasket aperture in whichcase the aperture edges of the first and second half subgaskets align.

The first half subgasket 230 has a first surface 231 oriented toward theelectrolyte membrane 210. An adhesive layer 250, comprising, e.g., apressure sensitive adhesive (PSA) or other type, is disposed on thefirst surface 231. The second half subgasket has a second surface 241oriented toward the electrolyte membrane 210. Substantial portions ofthe second surface 241 of the second half subgasket 240 have no adhesiveor the entire second surface 241 has no adhesive. An adhesive may bepresent on the second gasket surface, so long as substantial portions ofat least one of the first and second gasket surfaces oriented toward themembrane do not include an adhesive. Substantial portions devoid ofadhesive promote friction between the subgasket surfaces and themembrane for positional stability of the membrane during temperaturesand pressures associated with fuel cell operation. Although the secondsurface 241 of the second half subgasket does not have an adhesivelayer, it is adhesively attached to the first half subgasket via theadhesive layer 250 disposed on the first surface 231 of the first halfsubgasket. The second half subgasket is not adhesively attached to themembrane.

Electrolyte membrane 210 is “thrifted” in the x and y directions whichmeans that electrolyte membrane extends only partially under the halfsubgaskets 230, 240. Membrane thrifting as used herein refers toreducing the amount of electrolyte membrane used to form the fuel cellsubassembly by reducing the x and/or y dimensions of the electrolytemembrane.

FIG. 2D is a cross section of a subgasketed 5 layer membrane electrodeassembly

(MEA) 202 which includes the subgasketed electrolyte membrane 201, asdescribed in more detail in connection with FIGS. 2A-2C, and catalystcoated GDLs comprising catalyst layers 212, 213 disposed on GDLs 262,263.

FIG. 2E illustrates a portion of a subgasket 260 and membrane 210. Thesubgasket includes first and second half subgaskets 264, 265. First andsecond half subgaskets 264, 265 have first and second subgasket surfaces266, 267 oriented toward the membrane 210. In this example, the firstsurface 266 is substantially covered with a first adhesive layer 268.The second surface 267 has a second adhesive layer 269. However, asubstantial portion 261 of the second half subgasket surface 267 isdevoid of adhesive layer.

In some embodiments, the first half subgasket surface has adhesive overmost or all of the first have subgasket surface and the second halfsubgasket surface has no adhesive. FIG. 2F illustrates a subgasket 270having first and second half subgaskets 271, 272 deployed over amembrane 210. The first and second half subgaskets 271, 272 have firstand second subgasket surfaces 273, 274, respectively, oriented towardthe membrane 210. An adhesive layer 275 is disposed over most of thefirst half subgasket surface 273. The second subgasket surface 274 hasno adhesive.

In some embodiments, both subgasket surfaces have some portions withadhesive and both subgasket surfaces have substantial portions that donot have adhesive. FIG. 2G illustrates a subgasket 280 having first andsecond half subgaskets 281, 282 deployed over a membrane 210. The firstand second half subgaskets 281, 282 have first and second subgasketsurfaces 283, 284, respectively, oriented toward the membrane 210. Oneor more portions of the first subgasket surface 283 have an adhesivelayer 285. One or more portions of the second subgasket surface 284 havean adhesive layer 286. A substantial portion 287 of the first subgasketsurface 283 is devoid of adhesive. A substantial portion 288 of thesecond subgasket surface 284 is devoid of adhesive. For some subgasketedmembrane constructions, such as the constructions illustrated in FIGS.2F and 2G, no adhesive is present at either subgasket surface for atleast some portion of the interface between half subgaskets and/or theinterface between each subgasket layer and the membrane.

In some embodiments, at least one of the half subgaskets includes asurface treatment that reduces the amount of membrane movement betweenthe first and second half subgaskets. For example, the surface treatmentmay increase friction between the first and second subgasket surfacesthat face the membrane and/or may increase friction between thesubgasket surfaces and the membrane. Exemplary surface treatments mayinclude, for example, coronas, plasma treatments, primers, the presenceof microstructures on one or both surfaces of the subgasket that facethe membrane, and/or roughening one or both surfaces of the subgasketthat face the membrane and/or other treatments. Surface treatments canalso be added on opposite side of subgasket to increase adhesion ofadhesive to membrane or to plastic subgasket.

FIG. 2H illustrates a subgasketed membrane wherein at least a portion ofthe surface of the second half subgasket that faces the membrane has asurface treatment that increases friction and/or reduces the amount ofmembrane movement. A subgasket 290 includes first and second halfsubgaskets 291, 292 deployed over a membrane 210. The first and secondhalf subgaskets 291, 292 have first and second subgasket surfaces 293,294, respectively, oriented toward the membrane 210. One or moreportions of the first subgasket surface 293 have an adhesive layer 295.A substantial portion 296 of the second subgasket surface 294 has noadhesive. One or both of the subgasket surfaces 293, 294 includes asurface treatment 297 that reduces membrane movement. For example, thesurface treatment may increase friction between the membrane and thesurface 294 of the second half subgasket. The surface treatment 297 maybe present over substantially all of the subgasket surface 293, 294 oronly a portion of the subgasket surface.

FIGS. 3A and 3B are cross sections of fuel cell subassemblies 301 and302 respectively. Subassembly 301 is a subgasketed CCM and subassemblyand 302 is a subgasketed 5 layer MEA. Subassemblies 301 and 302 includea catalyst coated membrane (CCM) 311 disposed between subgasket 320. TheCCM 311 includes an electrolyte membrane 310 and catalyst layers 312,313. Subgasket 320 includes a first half subgasket 330 that has anadhesive 350 and a second half subgasket 340 without adhesive. Halfsubgaskets 330, 340 are perimeter subgaskets that have the form of aframe with apertures 333, 343 through which portions, i.e., the centerregion of the CCM 311, is exposed. Subassembly 302 includes subassembly301 with the addition of GDLs 362, 363 disposed on either side of thesubgasketed CCM 301. As illustrated in the cross sectional diagram ofFIGS. 3A and 3B, the CCM may be smaller in width than the width of theGDL. In other implementations, the CCM width may be larger than thewidth of the GDL or the CCM and GDL may have substantially equal widths.GDLs may be adhered using a suitable adhesive or bonded thermally to thesubgasketed CCM.

In some implementations, the electrolyte membrane or CCM may besubgasketed with only a half subgasket, as illustrated by the MEA 303depicted in FIG. 3C. In this exemplary implementation, MEA 303 includesa CCM 311 comprising an electrolyte membrane 310 and first and secondcatalyst layers 313, 313. A first half subgasket 330 has an adhesivelayer 350. No second half subgasket is used in these implementations.The MEA also includes GDLs 362, 363 which are installed over the halfgasketed CCM.

As illustrated in FIG. 4, fuel cell subassemblies 401 (e.g.,subassemblies illustrated in FIGS. 2-3 can be produced as a roll goodweb 400 of multiple concatenated subassemblies. A “web” as discussedherein and illustrated in FIG. 4 is an article having an x axisdimension that is much greater than its y axis dimension, and havingsufficient flexibility to be processed and stored as a roll. The rollgood web 400 may include, for example, many half subgasketed or fullysubgasketed fuel cell subassemblies 401, such as half or fullysubgasketed membranes or CCMs, five layer MEAs and/or other fuel cellsubassemblies 401. Multiple fuel cell subassemblies 401 may be disposedalong the x axis of the web 400 and multiple fuel cell subassemblies 401may be disposed across the y axis of the web 400. The roll good web 400can be wound on a roller 402, with an appropriate liner material, ifnecessary, and may be sold in rolled form. After formation of the fuelcell subassembly roll good web 400, the web 400 can be cut intoindividual fuel cell subassemblies 401, e.g., MEAs. The individual MEAsmay then be assembled into a fuel cell stack.

Roll good fuel cell subassembly webs can include electrolyte membranesand/or CCMs that are thrifted in both x and y directions in accordancewith embodiments of the invention. Membrane thrifting in the y directioninvolves reduction of the width of the membrane, which could be amembrane web or a CCM web, in the y direction (cross-web direction). Asillustrated in the following examples, membrane thrifting in the xdirection (down web direction) for roll good fuel cell subassembly websinvolves the use of multiple individual electrolyte membranes or CCMs toform multiple fuel cell subassemblies of a fuel cell subassembly web.

FIGS. 5A-5C illustrate a fuel cell subassembly web 500 comprising manyconcatenated fuel cell subassemblies, of which subassemblies 503A, 503B,503C are shown. Fuel cell subassembly web 500 is illustrated in anunrolled condition in plan view (FIG. 5A), cross section view along lineG-G′ (FIG. 5B), and cross section view along line H-H′ (FIG. 5C). Inthis implementation, multiple individual electrolyte membranes 510A,510B, 510C are used. Subgasket 520 comprises first and second halfsubgasket webs 530, 540. First and second half subgasket webs 530, 540have the form of a continuous ladder with apertures 533, 543 throughwhich center portions the electrolyte membranes 510A, 510B, 510C areexposed. Adhesive layer 550 is disposed on the surface 531 of the firsthalf subgasket web 530 that faces the individual electrolyte membranes510A, 510B, 510C. There is no adhesive disposed on substantial portionsof the surface 541 of the second half subgasket web 540 that faces theindividual electrolyte membranes 510A, 510B, 510C.

As can be seen in the cross section of FIG. 5B, the use of individualelectrolyte membranes 510A, 510B, 510C provides membrane thrifting inthe x direction because membrane material is conserved in regions 504between neighboring fuel cell subassemblies 503A, 503B, 503C. The use ofindividual membranes 510A, 510B, 510C also provides membrane thriftingin the y direction as illustrated by the cross section of FIG. 5C. Eachof the individual electrolyte membranes 510A, 510B, 510C conservemembrane material at regions 505 along the sides of the fuel cellsubassembly web 500 because the individual electrolyte membranes 510A,510B, 510C only extend partially under the subgasket 520 in the ydirection.

Membrane thrifting in the x and/or y directions conserves membranematerial in regions between neighboring fuel cell assemblies in a fuelcell assembly web and/or conserves membrane material in regions alongthe sides of the fuel cell assembly web. In these regions, theelectrolyte membrane extends under the subgasket to an extent necessaryto achieve good structural stability for the fuel cell subassembly web500 during manufacturing processes as well as good stability and sealingperformance of the fuel cell subassemblies 503A, 503B, 503B whenoperated in a fuel cell stack.

FIGS. 5D, 5E, and 5F illustrate plan, y direction, and x direction crosssectional view, respectively, of a five layer MEA web 502 formed byinstalling catalyst coated GDLs comprising GDLs 562A, 563A, 562B, 563B,562C, 563C and catalyst coatings 564A, 565A, 564B, 565B, 564C, 565C onthe fuel cell subassembly web 500.

In some embodiments, the first half subgasket web discussed above may bereplaced by a plurality of individual first half subgaskets 593A, 593B,593C, as illustrated in FIGS. 5G and 5H. FIGS. 5G and 5H illustrate afuel cell subassembly web 590 comprising many concatenated fuel cellsubassemblies, of which subassemblies 591A, 591B, 591C are shown. Fuelcell subassembly web 590 is illustrated in an unrolled condition in planview (FIG. 5G) and cross section view along line C-C′ (FIG. 5H). In thisimplementation, multiple individual electrolyte membranes 592A, 592B,592C are used. The fuel cell subassembly web 590 includes a number ofindividual first half subgaskets 593A, 593B, 593C, each having anaperture 598A, 598B, 598C through with center portions of theelectrolyte membranes 592A, 592B, 592C are exposed. Each of theindividual first half subgaskets 593A, 593B, 593C include adhesivelayers 595A, 595B, 595C disposed on the first half subgasket surfaces594A, 594B, 594C that face the individual electrolyte membranes 592A,592B, 592C. The fuel cell subassembly web includes a second halfsubgasket web 596, which includes a number of apertures 599 throughwhich center portions of the electrolyte membranes 592A, 592B, 592C areexposed. There is no adhesive disposed on substantial portions of thesurface 597 of the second half subgasket web 596 that faces theindividual electrolyte membranes 592A, 592B, 592C.

FIGS. 5I and 5J illustrate plan and y direction cross sectional views,respectively, of a five layer MEA web 575 formed by installing catalystcoated GDLs comprising GDLs 562A, 563A, 562B, 563B, 562C, 563C andcatalyst coatings 564A, 565A, 564B 565B, 564C, 565C on the fuel cellsubassembly web 590.

FIGS. 6A-6C illustrate a fuel cell subassembly web 600 with CCMthrifting in x and y directions. Fuel cell subassembly web 600 comprisesmany concatenated fuel cell subassemblies, of which subassemblies 603A,603B, 603C are shown. Fuel cell subassembly web 600 is illustrated in anunrolled condition in plan view (FIG. 6A), cross section view along lineI-I′ (FIG. 6B), and cross section view along line J-J′ (FIG. 6C). Inthis implementation, multiple individual CCMs 611A, 611B, 611C are used.The individual CCMs 611A, 611B, 611C include individual electrolytemembranes 610A, 610B, 610C with catalyst layers 612A, 613A, 612B, 613B,612C, 613C.

Subgasket 620 comprises first and second half subgasket webs 630, 640.First and second half subgasket webs 630, 640 have the form ofcontinuous ladders with apertures 633, 643 through which center portionsthe CCMs 611A, 611B, 611C are exposed. Adhesive layer 650 is disposed onthe surface 631 of the first half subgasket web 630 facing theindividual CCMs 611A, 611B, 611C. Substantial portions of the secondhalf subgasket web 640 has no adhesive on the surface 641 facing theindividual CCMs 611A, 611B, 611C, e.g., the surface 641 is devoid ofadhesive. FIGS. 6D, 6E, and 6F illustrate a five layer MEA web 602 thatis formed using the fuel cell subassembly web 600 after installation ofthe GDLs 662A, 663A, 662B, 663B, 662C, 663C.

FIGS. 6G and 6H illustrate a fuel cell subassembly web 690 havingindividual first half subgaskets 693A, 693B, 693C in place of the firstsubgasket web illustrated in

FIGS. 6A-6F. Fuel cell subassembly web 690 comprises many concatenatedfuel cell subassemblies, of which subassemblies 691A, 691B, 691C areshown. Fuel cell subassembly web 690 is illustrated in an unrolledcondition in plan view (FIG. 6G), and in a cross section view along lineD-D′ (FIG. 6H). In this implementation, multiple individual CCMs 611A,611B, 611C are used. The individual CCMs 611A, 611B, 611C includeindividual electrolyte membranes 610A, 610B, 610C with catalyst layers612A, 613A, 612B, 613B, 612C, 613C.

The fuel cell subassembly web 690 includes a number of individual firsthalf subgaskets 693A, 693B, 693C, each having an aperture 698A, 698B,698C through with center portions of the CCMs 611A, 611B, 611C areexposed. Each of the individual first half subgaskets 693A, 693B, 693Cinclude adhesive layers 695A, 695B, 695C disposed on the surfaces 694A,694B, 694C of the first half subgaskets 693A, 693B, 693C that face theindividual CCMs 611A, 611B, 611C. The fuel cell subassembly web 690includes a second half subgasket web 696, which is a web having a numberof apertures 699 through which center portions of the individual CCMs611A, 611B, 611C are exposed. A substantial portion of the surface 697of the second half subgasket web 696 that faces the individual CCMs611A, 611B, 611C is devoid of adhesive.

FIGS. 6I and 6J illustrate plan and y direction cross sectional views,respectively, of a five layer MEA web 675 formed by installing GDLs662A, 663A, 662B, 663B, 662C, 663C on the fuel cell subassembly web 690.

The use of a subgasket with single sided adhesive may be desirable insome applications as previously discussed. In other applications, it maybe useful to include a subgasket with adhesive on both subgasket layersused with membranes thrifted in both x and y directions. FIGS. 7A-7J and8A-8J illustrate fuel cell subassembly webs that include x and ydirection membrane thrifting and subgaskets with adhesive on both firstand second half subgaskets.

Fuel cell subassembly web 700 and five layer MEA web 702 illustrated inFIGS. 7A-7F comprise many concatenated fuel cell subassemblies, of whichsubassemblies 703A, 703B, 703C are shown. Fuel cell subassembly web 700and MEA web 702 are illustrated in an unrolled condition in plan views(FIGS. 7A and 7D, respectively), cross section views along line K-K′(FIGS. 7B and 7E, respectively), and cross section views along line L-L′(FIGS. 7C and 7F, respectively). Fuel cell subassembly web 700 usesmultiple individual electrolyte membranes 710A, 710B, 710C. Subgasket720 comprises first and second half subgasket webs 730, 740. Each of thefirst and second half subgasket webs 730, 740 have the form of acontinuous ladder with apertures 733, 743 through which center portionsthe individual electrolyte membranes 710A, 710B, 710C are exposed.

Adhesive layer 753 is disposed on surface 731 of first half subgasketweb 730 which is oriented toward electrolyte membranes 710A, 710B, 710C.Adhesive layer 754 is disposed on surface 741 of second half subgasketweb 740 which is oriented toward electrolyte membranes 710A, 710B, 710C.FIGS. 7D, 7E, and 7F illustrate plan, y direction cross section, and xdirection cross section views, respectively of a five layer MEA web 702formed using the fuel cell subassembly web 700 after installation ofcatalyst coated GDLs. The catalyst coated GDLs include GDLs 762A, 763A,762B, 763B, 762C, 763C having catalyst coatings 764A, 765A, 764B, 765B,764C, 765C.

In some embodiments, the first half subgasket web discussed inconnection with FIGS. 7A-7F may be replaced by a plurality of individualfirst subgaskets 793A, 793B, 793C as illustrated in FIGS. 7G and 7H.FIGS. 7G and 7H illustrate a fuel cell subassembly web 790 comprisingmany concatenated fuel cell subassemblies, of which subassemblies 791A,791B, 791C are shown. Fuel cell subassembly web 790 is illustrated in anunrolled condition in plan view (FIG. 7G) and cross section view alongline D-D′ (FIG. 7H). In this implementation, multiple individualelectrolyte membranes 792A, 792B, 792C are used. The fuel cellsubassembly web 790 includes a number of individual first halfsubgaskets 793A, 793B, 793C, each having an aperture 798A, 798B, 798Cthrough with center portions of the electrolyte membranes 792A, 792B,792C are exposed. Each of the individual first half subgaskets 793A,793B, 793C include adhesive layers 795A, 795B, 795C disposed on thesurfaces 794A, 794B, 794C of the first half subgaskets that face theindividual electrolyte membranes 792A, 792B, 792C. The fuel cellsubassembly web includes a second half subgasket web 796, which includesa number of apertures 799 through which center portions of theelectrolyte membranes 792A, 792B, 792C are exposed. There is an adhesivelayer 785 disposed on the surface 797 of the second half subgasket web796 that faces the individual electrolyte membranes 792A, 792B, 792C.

FIGS. 71 and 7J illustrate plan and y direction cross sectional views,respectively, of a five layer MEA web formed by installing catalystcoated GDLs comprising GDLs 762A, 763A, 762B, 763B, 762C, 763C andcatalyst coatings 764A, 765A, 764B 765B, 764C, 765C on the fuel cellsubassembly web 790.

Fuel cell subassembly web 800 illustrated in FIGS. 8A-8F is similar tofuel cell subassembly web 700 except that subassembly web 800 includesindividual CCMs rather than individual electrolyte membranes withoutcatalyst coatings as in FIGS. 7A-7F. FIGS. 8A-8C illustrate concatenatedfuel cell subassemblies 803A, 803B, 803C. Fuel cell subassembly webs800, 802 are illustrated in an unrolled condition in plan views (FIGS.8A and 8D, respectively), cross section views along line M-M′ (FIGS. 8Band 8E, respectively), and cross section views along line N-N′ (FIGS. 8Cand 8F, respectively). In this implementation, multiple individual CCMs811A, 811B, 811C are used. The individual CCMs 811A, 811B, 811C compriseindividual electrolyte membranes 810A, 810B, 810C having catalyst layers812A, 813A, 812B, 813B, 812C, 813C. Subgasket 820 comprises first andsecond half subgasket webs 830, 840. Each of the first and second halfsubgasket webs 830, 840 have the form of a continuous ladder withapertures 833, 843 through which center portions the individualelectrolyte membranes 811A, 811B, 811C are exposed.

Adhesive layer 853 is disposed surface 831 of first subgasket web 830which is oriented toward CCMs 811A, 811B, 811C. Adhesive layer 854 isdisposed on surface 841 of second half subgasket web 840 which isoriented toward CCMs 811A, 811B, 811C. FIGS. 8D, 8E, and 8F illustrate afive layer MEA web 802 that includes the fuel cell subassembly web 800and GDLs 862A, 863A, 862B, 863B, 862C, 863C.

FIGS. 8G and 8H illustrate a fuel cell subassembly web 890 havingindividual first half subgaskets 893A, 893B, 893C in place of the firsthalf subgasket web illustrated in FIGS. 8A-8F. Fuel cell subassembly web890 comprises many concatenated fuel cell subassemblies, of whichsubassemblies 891A, 891B, 891C are shown. Fuel cell subassembly web 890is illustrated in an unrolled condition in plan view (FIG. 8G), and in across section view along line E-E′ (FIG. 8H). In this implementation,multiple individual CCMs 811A, 811B, 811C are used. The individual CCMs811A, 811B, 811C include individual electrolyte membranes 810A, 810B,810C with catalyst layers 812A, 813A, 812B, 813B, 812C, 813C.

The fuel cell subassembly web 890 includes a number of individual firsthalf subgaskets 893A, 893B, 893C, each having an aperture 898A, 898B,898C through with center portions of the individual CCMs 811A, 811B,811C are exposed. Each of the individual first half subgaskets 893A,893B, 893C include adhesive layers 895A, 895B, 895C disposed on thesurfaces 894A, 894B, 894C of the first half subgaskets 893A, 893B, 893Cthat face the individual electrolyte membranes 811A, 811B, 811C. Thefuel cell subassembly web 890 includes a second half subgasket web 896,which has a number of apertures 899 through which center portions of theindividual CCMs 811A, 811B, 811C are exposed. The surface 897 of thesecond half subgasket web 896 that faces the individual CCMs 811A, 811B,811C includes an adhesive layer 885.

FIGS. 8I and 8J illustrate plan and y direction cross sectional views,respectively, of a five layer MEA web 875 formed by installing GDLs862A, 863A, 862B, 863B, 862C, 863C on the fuel cell subassembly web 890.

The subgaskets described herein may comprise various types of polymermaterial, such as polyester, such as polyethylene naphthalate (PEN) orpolyethylene telephthalate (PET), polyimide, and/or other similarmaterials, including rigid polymeric materials that are sufficientlythin, sufficiently strong, and sufficiently compatible with the fuelcell environment, i.e., temperatures of 60-120° C., in the presence ofwater, hydrogen and/or oxygen. In one example, the subgasket materialhas a thickness greater than about 0.0125 mm. In one embodiment, thesubgasket material is PEN having a thickness of about 0.1 mm. Thesubgasket can optionally have a gasket or seal adhered to one or bothouter surfaces. The gasket material may include microstructuredelastomeric ribs, such as thermally cured ethylene propylene dienemonomer (EPDM) elastomeric ribs. The first and second half subgasketsneed not have identical characteristics. The characteristics of the halfsubgaskets may be selected to facilitate component handling or fuel celloperation. For example, in certain embodiments, the first half subgasketmay have a different thickness from the second half subgasket and/or thefirst half subgasket may comprise one or more materials that aredifferent from those of the second half subgasket.

The materials of the subgaskets and the adhesive layers are selected sothat the adhesive layers adhere well to the subgasket surface. Thethickness of the adhesive layer (if used) may be about 0.005 to about0.05 mm. The adhesive layers may comprise a pressure sensitive adhesive(PSA), a heat activated adhesive, a UV activated adhesive, or other typeof adhesive. For example, the adhesive layer may comprise any of thefollowing: acrylic PSA's, rubber based adhesives, ethylene maleicanhydride copolymers, olefin adhesives such as copolymers of 1-octenewith ethylene or propylene, nitrile based adhesives, epoxy basedadhesives, and urethane based adhesives. In other embodiments, theadhesive layer may comprise a thermally activated adhesive, such asThermobond 845 (polyethylene maleate based) and Thermobond 583 (nitrilerubber based).

The adhesive may comprise a crosslinked adhesive that has high tack. Forexample a the adhesive may be an acrylate pressure sensitive adhesiveformulated to be hydrolytically stable and creep resistant whencompressed in the fuel cell stack. The adhesive and the subgasket layer,e.g., PEN layer, may be rolled up with a release liner and subsequentlyused to form the subgasketed fuel cell subassemblies described herein.

Any suitable electrolyte membrane may be used in the practice of thepresent invention. Useful PEM thicknesses range between about 200 μm andabout 1 μm. Copolymers of tetrafluoroethylene (TFE) and a co-monomeraccording to the formula: FSO2-CF2-CF2-O-CF(CF3)-CF2-O-CF=CF2 are knownand sold in sulfonic acid form, i.e., with the FSO2-end group hydrolyzedto HSO3-, under the trade name NAFION® by DuPont Chemical Company,Wilmington, Del. NAFION® is commonly used in making polymer electrolytemembranes for use in fuel cells. Copolymers of tetrafluoroethylene (TFE)and a co-monomer according to the formula: FSO2-CF2-CF2-O-CF=CF2 arealso known and used in sulfonic acid form, i.e., with the FSO2-end grouphydrolyzed to HSO3-, in making polymer electrolyte membranes for use infuel cells. Most preferred are copolymers of tetrafluoroethylene (TFE)and FSO2-CF2CF2CF2CF2-O-CF=CF2, with the FSO2-end group hydrolyzed toHSO3-.

In some embodiments, the catalyst layers may comprise Pt or Pt alloyscoated onto larger carbon particles by wet chemical methods, such asreduction of chloroplatinc acid. This form of catalyst is dispersed withionomeric binders and/or solvents to form an ink, paste, or dispersionthat is applied either to the membrane, a release liner, or GDL.

In some embodiments, the catalyst layers may comprise nanostructuredsupport elements bearing particles or nanostructured thin films (NSTF)of catalytic material. Nanostructured catalyst layers do not containcarbon particles as supports and therefore may be incorporated into verythin surface layers of the electrolyte membrane forming a densedistribution of catalyst particles. The use of nanostructured thin film(NSTF) catalyst layers allows much higher catalyst utilization thancatalyst layers formed by dispersion methods, and offer more resistanceto corrosion at high potentials and temperatures due to the absence ofcarbon supports. In some implementations, the catalyst surface area of aCCM may be further enhanced by using an electrolyte membrane havingmicrostructured features. NSTF catalyst layers comprise elongatednanoscopic particles that may be formed by vacuum deposition of catalystmaterials on to acicular nanostructured supports. Nanostructuredsupports suitable for use in the present invention may comprise whiskersof organic pigment, such as C.I. PIGMENT RED 149 (perylene red). Thecrystalline whiskers have substantially uniform but not identicalcross-sections, and high length-to-width ratios. The nanostructuredsupport whiskers are coated with coating materials suitable forcatalysis, and which endow the whiskers with a fine nanoscopic surfacestructure capable of acting as multiple catalytic sites. In certainimplementations, the nanostructured support whiskers may be extendedthrough continued screw dislocation growth. Lengthening thenanostructured support elements allows for an increased surface area forcatalysis.

The nanostructured support whiskers are coated with a catalyst materialto form a nanostructured thin film catalyst layer. According to oneimplementation, the catalyst material comprises a metal, such as aplatinum group metal. In one embodiment, the catalyst coatednanostructured support elements may be transferred to a surface of anelectrolyte membrane to form a catalyst coated membrane. In anotherembodiment, the catalyst coated nanostructured support elements maybeformed on a GDL surface.

The GDLs can be any material capable of collecting electrical currentfrom the electrode while allowing reactant gasses to pass through,typically a woven or non-woven carbon fiber paper or cloth. The GDLsprovide porous access of gaseous reactants and water vapor to thecatalyst and membrane, and also collect the electronic current generatedin the catalyst layer for powering the external load.

The GDLs may include a microporous layer (MPL) and an electrode backinglayer (EBL), where the MPL is disposed between the catalyst layer andthe EBL. EBLs may be any suitable electrically conductive poroussubstrate, such as carbon fiber constructions (e.g., woven and non-wovencarbon fiber constructions). Examples of commercially available carbonfiber constructions include trade designated “AvCarb P50” carbon fiberpaper from Ballard Material Products, Lowell, MA; “Toray” carbon paperwhich may be obtained from ElectroChem, Inc., Woburn, Mass. EBLs mayalso be treated to increase or impart hydrophobic properties. Forexample, EBLs may be treated with highly-fluorinated polymers, such aspolytetrafluoroethylene (PTFE) and fluorinated ethylene propylene (FEP).

The carbon fiber constructions of EBLs generally have coarse and poroussurfaces, which exhibit low bonding adhesion with catalyst layers. Toincrease the bonding adhesion, the microporous layer may be coated tothe surface of EBLs. This smoothens the coarse and porous surfaces ofEBLs, which provides enhanced bonding adhesion with some types ofcatalyst layers.

Fuel cell subassembly webs, e.g., fuel cell subassembly webs 500, 590,600, 690, 700, 790, 800, 890 illustrated in FIGS. 5A-5C, 5G, 5H, 6A-6C,6G, 6H, 7A-7C, 7G, 7H, 8A-8C, 8G, 8H can be made using roll-to-rollmanufacturing processes. Installation of GDLs to form 5-layer MEAsubassembly webs 502, 575, 602, 675, 702, 775, 802, 875 as illustratedin FIGS. 5D-5F, 5I, 5J, 6D-6F. 61, 6J, 7D-7F, 7I, 7J, 8D-8F, 8I, 8J canalso be performed in roll-to-roll processes.

A flow diagram of a roll-to-roll process for manufacture of subgasketedfuel cell subassembly webs, e.g., subgasketed electrolyte membrane webs,subgasketed CCM webs and/or subgasketed five layer MEA webs isillustrated in FIG. 9. FIG. 9 illustrates the manufacture of a fivelayer MEA web that incorporates a CCM. It will be appreciated that asimilar process may be used to form a five layer MEA subassembly websusing catalyst coated GDLs rather than CCMs.

Optionally, a continuous CCM web is formed 910 by lamination of anodeand cathode catalysts to an electrolyte membrane. If an electrolytemembrane web without catalyst coating is used with catalyst coated GDLsto form the MEA, this part of the process may be eliminated. Themembrane web is cut into individual membranes which are adhered 920 to afirst adhesive layer disposed on a first half subgasket ladder web.Lamination of the individual membranes to the first half subgasketladder web forms a half gasketed web with individual electrolytemembranes. A second half subgasket ladder web with little or no adhesivedisposed on the surface oriented toward the electrolyte membranes isattached 930 to the half subgasketed individual membrane web. The secondhalf subgasket ladder web is adhered the half subgasketed web by theadhesive layer disposed on the first half subgasket web. Optionally,GDLs are attached 940 to the subgasketed membrane web to form a fivelayer MEA web. If the subgasketed membrane web is not a CCM web then theGDLs include catalyst layers. The five layer MEA web may be cut to formindividual five layer MEAs.

FIGS. 10A-10D illustrate various subsystems of a roll-to-roll basedsystem configured to produce x and y thrifted fuel cell subassembliesincluding half subgasketed individual membrane webs, fully subgasketedindividual membrane webs, individual subgasketed membranes, five layerMEA webs, individual five layer MEAs, and various intermediate fuel cellsubassemblies. The fuel cell subassemblies, e.g., full or halfsubgasketed webs having multiple individual electrolyte membranes orCCMs and/or five layer MEA webs, may be produced as roll goods asillustrated by FIG. 4. A roll-to-roll based system is configured toimplement at least some processes using a roll-based approach, but notevery subsystem needs to be roll-based and/or not all input components,output components, and/or intermediate components need to be wound ontorolls and/or unwound from rolls. In connection with the manufacturingprocesses illustrated in FIGS. 10A-10D, some x direction (down web)cross sections of input, intermediate, and/or output subassembly webs orsubassemblies are shown in FIGS. 11A-11N to assist in understanding thestructure of the intermediate subassembly webs or subassemblies.

FIG. 10A illustrates a subsystem 1000 configured to produce a CCM web1005. Cathode and anode catalyst layers 1002, 1003, which are depositedor coated onto temporary carrier webs are laminated onto an electrolytemembrane web 1001 by lamination rolls 1008 and 1009. The carrier webs1095, 1096 are peeled away, e.g., by duck bill peeler 1007 to form CCMweb 1005. A cross sectional diagram of the CCM web 1005 is shown in FIG.11A. The CCM web 1005 includes the electrolyte membrane 1102 with ananode catalyst 1101 disposed on one surface of the electrolyte membrane1102 and a cathode catalyst 1103 disposed on the opposite surface of theelectrolyte membrane 1102. The CCM web 1005 produced by subsystem 1000is input to subsystem 1010 illustrated in FIG. 10B for attachment of thefirst half subgasket. Alternatively an electrolyte web without catalystlayers is input to subsystem 1010.

The subsystem 1010 uses an anvil roll 1011 and a foamed vacuum die 1012to cut the membrane web 1005 (or electrode membrane without catalyst)into individual membranes 1021 a, 1021 b. The membrane web 1005 is cutinto individual membranes 1021 a, 1021 b as it passes between the anvilroll 1011 and a foamed vacuum die 1012. A more detailed view of thefoamed vacuum die 1012 is illustrated in FIGS. 13A and 13B.

Prior to cutting, the membrane web may optionally be pre-treated topresent the membrane web 1005 to the die 1012 in a condition thatachieves more uniform cutting. Membrane pre-treatment options areillustrated in FIGS. 12A and 12B. For example, one pre-treatmentoperation (FIG. 12A) involves the use of a pre-treatment roller 1201with bumpers 1203, which may be formed by a wrap of tape or similarmethod, on either side of the pre-treatment roller 1201. The operationof the pre-treatment roller 1201 with bumpers 1203 is to slightly spreadthe membrane web 1005 prior to the cutting operation to achieve a morerepeatable cut. Alternatively, or additionally, as illustrated in FIG.12B, the membrane web 1005 may be heated slightly, e.g., by a forced airheater or other type of heater 1202, to reduce moisture and/or toslightly shrink the membrane web 1005 prior to the cutting operation.

The scrap membrane ladder 1004 from the membrane cutting process isdiscarded. A plan view of the scrap membrane ladder 1004 is shown inFIG. 11B. To achieve cost reductions by reducing utilization of membranematerial, the vacuum die 1012 can be configured and the cutting processcontrolled so that the thickness of the rungs, d₁, and/or sides, d₂, ofthe scrap membrane ladder 1004 may be less than ⅛ inches or may be evenbe reduced to 0 inches in some implementations with careful control ofthe cutting process. The individual membranes 1021 a, 1021 b are held ondie 1012 by vacuum as it rotates towards the lamination roller 1013.

As illustrated by the cross section diagram of FIG. 11C, a first halfsubgasket web 1016 includes a first subgasket layer 1106 and an adhesivelayer 1107 with a release liner 1108. The first half subgasket web 1016is input to the subsystem 1010 on a carrier web 1105, e.g., a carrierweb having a repositionable adhesive. In some implementations, a vacuumbelt could be used to transport the first half subgasket web (includingthe carrier web) to subsystem 1010. The carrier web with repositionableadhesive serves to support and stabilize the first half subgasket web1016. The repositionable carrier web is a web including an adhesive withadhesive tack properties sufficiently low so that the carrier web can beeasily removed from the first half subgasket web (or other work product)and the adhesive stays on the carrier web. In some implementations, thecarrier web is a 1 mil plastic or paper film with a 0.5 mil low tackadhesive on the surface of the film.

Returning to FIG. 10B, as the first half subgasket web 1016 movesbetween the anvil roll 1015 and subgasket die roll 1014 the die roll1014 makes aperture cuts in the first subgasket web 1016 that define thefirst subgasket web apertures while leaving the carrier web intact. Thefirst half subgasket material, adhesive, and adhesive release liner isinitially retained in the apertures as aperture slugs. A cross sectionof the first subgasket web 1017 after the cutting operation whichproduces the retained aperture slugs 1109 is shown in FIG. 11D. Theaperture slugs 1109 (cutout subgasket material, adhesive, and adhesiveliner remaining in the subgasket apertures) are initially left in place,but are eventually removed to reveal the apertures of the first halfsubgasket web. The adhesive release liner ladder 1018 is removed atroller 1019, leaving the first half subgasket web (with the apertureslugs intact minus the adhesive release liner ladder) 1020 on thecarrier web. The adhesive release liner ladder 1018 is shown in planview in FIG. 11E. A cross section of the first half subgasket web 1020with the aperture slug 1109 intact minus the adhesive release linerladder 1018 is shown in FIG. 11F. The first half subgasket web 1020 ison carrier web 1105 and includes the first half subgasket layer 1106 andadhesive layer 1107. A portion of the adhesive liner 1108 remains on theadhesive layer 1107. Portions of the surface 1107 a, 1107 b of theadhesive layer 1107 are exposed. As illustrated in FIG. 11F, a portionof the adhesive release liner 1108 is retained on the adhesive layer1107 in the region of the aperture slugs 1109. The individual membranes1021 a, 1021 b and the first half subgasket web (with the aperture slugsintact minus the adhesive release liner ladder) 1020 are broughttogether at the lamination roll 1013.

The foamed vacuum die 1012 (as illustrated in more detail in FIGS. 13Aand 13B) includes a porous, compliant material, e.g., foam, in the diecavities of the die 1012 to hold and protect the membranes from damageduring the manufacturing process. During the attachment of the to theindividual membranes 1021 a, 1021 b to the subgasket web 1021, it isdesirable that no foam is present on the foamed vacuum die 1012 in thegaps (see 1315, FIG. 13) between the die cavities. The absence ofmaterial on the die in the gaps 1315 allows the first half subgasket web1020 to advance through nip of 1013, 1012 while the foamed vacuum die1012 and anvil roll 1011 are stopped when the gap between apertures inthe subgasket web 1020 is aligned with lamination roll 1013. The foamedvacuum die 1012 resumes line speed when an individual membrane isregistered to the aperture in the subgasket web 1020. A process controlmodule 1099 includes one or more sensors and circuitry configured tocontrol the operation of subsystems illustrated in FIGS. 10A-10E. Forexample, the process control module 1099 may include sensors andcircuitry configured to adjust the speed of one process relative to thespeed of another process and/or to control the down web position of oneor more webs used in fabrication of the fuel cell subassemblies.Further, the process control module 1099 may include sensors andcircuitry to control the cross web position of one or more webs. Downweb and/or cross web position control facilitates proper alignment offuel cell subassembly webs and/or components.

A sensor on the subgasket die 1014 is used to start or stop the foamedvacuum die 1012 that cuts the individual membranes 1021 a, 1021 b tocontrol the alignment of the individual membranes 1021 a, 1021 b inrelation to the aperture cuts in the first subgasket web 1020 atlamination roller 1013. The pressure sensitive adhesive on the firstsubgasket web 1020, which is exposed by removal of the release linerladder 1018, adheres the first subgasket web 1020 to the individualmembranes 1021 a, 1021 b to form a half subgasketed membrane web 1025.At this stage, the half subgasketed membrane web 1025 retains theaperture slugs. The individual membranes 1021 a, 1021 b are adhered tothe first subgasket web 1020 at the perimeter surface regions of theindividual membranes 1021 a, 1021 b with the center surface regions ofthe individual membranes 1021 a, 1021 b being protected from theadhesive by the adhesive release liner of the aperture slugs.

A cross section of the half subgasketed membrane web (with the apertureslugs retained) 1025 on the carrier web 1105 is shown in FIG. 11G. Thehalf subgasketed membrane web 1025 includes the first subgasket layer1106 and adhesive layer 1107. A portion of the adhesive liner 1108remains on the adhesive 1107. Portions of the surface 1117 of theadhesive layer 1107 are now attached to the membrane 1021 a. At thisstage of the process, the aperture slugs 1109 are retained.

FIG. 10C illustrates a subsystem 1030 configured to cut the halfsubgasketed membrane web 1025 into individual half subgasketed membranesand to attach the second subgasket web to the individual halfsubgasketed membranes. The process of subsystem 1030 can be used toproduce subgasketed membranes with the second subgasket frame having alarger size than first subgasket frame after cutting the subgasketedmembrane web into individual subgasketed membranes.

The half subgasketed membrane web (with the aperture slugs retained)1025 is input to subsystem 1030. The aperture slugs 1109 andrepositionable carrier web 1105 are removed at roller 1026 leaving ahalf subgasketed membrane web 1028. Cross sectional views of theaperture slugs 1109 and repositionable carrier web 1105 (referred totogether as 1027) and the half subgasketed membrane web 1028 areillustrated in FIGS. 11H and 11I, respectively. Removal of the apertureslugs 1109 and carrier web 1105 (referred to together as 1027) shown inFIG. 11H leaves a half subgasketed membrane web 1028. The halfsubgasketed membrane web 1028 is illustrated by the cross sectional viewof FIG. 11I and the plan view of FIG. 11J. The half subgasketed membraneweb 1028 comprises multiple individual membranes (1021 a shown in FIG.11I and 1021 a-1021 d shown in FIG. 11J) held together by the ladderstructure of the first subgasket ladder web 1106 which is adhered to theperimeter surface regions of the individual membranes 1021 a-1021 d bythe adhesive 1107.

Individual half subgasketed membranes 1035 are cut out of the halfsubgasketed membrane web 1028 as the half subgasketed membrane web 1028passes between the patterned anvil roll 1031 and vacuum die 1032. Thescrap subgasket ladder 1036 left over from the cut is discarded. Theindividual half subgasketed membranes 1035 a, 1035 b are carried by thevacuum die 1032 to foam lamination roll 1033.

The second half subgasket web 1041 (without an adhesive layer) is inputto subsystem 1030 on a second carrier web, e.g., a carrier web having arepositionable adhesive. A cross section of the second half subgasketweb 1041 and carrier web 1110 is illustrated in the cross sectionaldiagram, FIG. 11K. Aperture cuts are made in the second gasket web 1041as it passes between die and anvil rollers 1043, 1044 forming apertureslugs. The cut portions of the second half gasket material forming theaperture slugs are left in place on the second carrier web 1110. A crosssection of the second subgasket web 1042 (with the aperture slugs 1111in place) on the carrier web 1110 is illustrated in the cross sectionaldiagram of FIG. 11L.

The second half subgasket web 1042 is laminated to the individual halfsubgasketed membranes 1035 at lamination roller 1033 to form a fullysubgasketed membrane web 1045 disposed on the second carrier web. Across section of the fully subgasketed membrane web 1045 on the carrierweb 1110 is illustrated in FIG. 11M. The fully subgasketed membrane web1045 includes the second half subgasket web 1041 with the aperture slugs1111 intact. The individual half subgasketed membrane webs 1035including the individual membranes 1021 a are adhered to the second halfsubgasket web 1041 by the adhesive layer 1107 a which is disposed on theindividual first half subgasket 1106 a. The second carrier web 1110 andaperture slugs 1111 are removed to reveal a subgasketed individualmembrane web. The subgasketed individual membrane web includes thriftedindividual electrolyte membranes subgasketed with individual first halfsubgaskets and a second half subgasket web. The individual first halfsubgaskets are adhered to the second half subgasket web and to theindividual membranes by an adhesive layer disposed on the individualfirst half subgaskets. The second half subgasket web may have little orno adhesive on the surface facing the electrolyte membrane. The processof subsystem 1030 can be used to produce a subgasketed membrane with thesecond subgasket frame larger than the first subgasket frame aftercutting the subgasketed membrane web into individual subgasketedmembranes. One individual subgasketed membrane 1049 a is illustrated bythe cross sectional diagram of FIG. 11N. The individual subgasketedmembrane 1049 a includes membrane 1021 a, first half subgasket 1106 ahaving adhesive layer 1107 a and second half subgasket 1041 a having noadhesive layer. Note that the first and second half subgaskets 1106 a,1041 a are not necessarily the same size, e.g., the first half subgasket1106 a may be smaller than the second half subgasket 1041 a as depictedin FIG. 11N.

FIG. 10D illustrates an alternate subsystem 1050 configured to registerand attach subgasketed membrane web 1025 illustrated by FIG. 11G to halfsubgasketed web 1042 illustrated in FIG. 11K. The subsystem 1050 of FIG.10D can be used in place of the subsystem 1030 of FIG. 10C, for example.The process of subsystem 1050 can be used to produce a subgasketedmembrane with the second subgasket outer perimeter the same size as thefirst subgasket outer perimeter after cutting the subgasketed membraneweb into individual subgasketed membranes.

The half subgasketed membrane web (with the aperture slugs intact) 1025(illustrated in the cross section of FIG. 11G) is input to subsystem1050. The aperture slugs and repositionable carrier web 1027 are removedat roller 1051. A cross sectional view of the aperture slugs andrepositionable carrier web 1027 is illustrated in FIG. 11H.

The second subgasket web 1041 (with or without an adhesive layer) isinput to subsystem 1050 on a carrier web, e.g., a carrier web having arepositionable adhesive A cross section of the second subgasket web 1041and carrier web 1110 is illustrated in FIG. 11K. Aperture cuts are madein the second subgasket web 1041 as the second subgasket web 1041 passedbetween die and anvil rollers 1053, 1054. If an adhesive layer is used,the release liner ladder for the adhesive layer is stripped away atroller 1057. The second gasket web material forming the aperture slugsis left in place on the carrier web. A cross section of the secondsubgasket web 1041 on the carrier web with the aperture slugs in place1042 is illustrated in FIG. 11L.

The half subgasketed membrane web 1025 is laminated to the secondsubgasket web 1042, which is on the carrier web 1110 with the apertureslugs 1111 still in place, as these components pass between roll 1051and foam or rubber lamination roll 1058. A cross section of thesubgasketed membrane web 1045 produced by subsystem 1050 is illustratedin FIG. 11M.

Subsystem 1060 illustrated in FIG. 10E may be used to attach GDLs to asubgasketed membrane web. If an electrolyte membrane without catalyst isused, then the GDLs used for this step may be catalyst coated. If a CCMmembrane is used, the GDLs attached in this step may not need catalystlayers. A first GDL web 1061 is input to the subsystem 1060 and anadhesive 1062 is optionally adhered to the GDL web 1061 at roller 1063.The adhesive may be double stick transfer adhesive, dispensed liquid, ora thermally activated adhesive, for example. The adhesive layer may forma porous electrically conductive layer on the GDL web 1061, e.g., if theadhesive is applied across the width of the GDL. The first adhesive GDLweb 1067 (first GDL web 1061 plus adhesive 1062) is cut into individualadhesive GDLs 1066 a, 1066 b as the first adhesive GDL web 1067 passesbetween die and anvil rollers 1064, 1065. The individual adhesive GDLs1066 a, 1066 b are transported to lamination rolls 1081, 1082, e.g., ona vacuum belt or carrier web.

A second GDL web 1071 is input to the subsystem 1060 and an adhesive1072 layer is adhered to the GDL web 1071 at roller 1073. The adhesivemay be double stick tape, dispensed liquid, or a thermally activatedadhesive, for example. The adhesive layer forms a porous electricallyconductive layer on the GDL web 1071. The second adhesive GDL web 1068(GDL web 1071 plus adhesive 1072) is cut into individual adhesive GDLs1076 a, 1076 b as the second adhesive GDL web 1068 passes between dieand anvil rollers 1074, 1075. The individual adhesive GDLs 1076 a, 1076b can be transported to lamination rolls 1081, 1082 on a vacuum belt orcarrier web.

A subgasketed CCM or electrolyte membrane web 1085, e.g., a subgasketedCCM or electrolyte membrane web as described in connection with FIG. 10is input to subsystem 1060. The second carrier web with the aperturesslugs is peeled away at roll 1088. In some implementations, roll 1088may be replaced by an angled peel bar. The individual adhesive GDLs 1066a, 1066 b, 1076 a, 1076 b are laminated to the subgasketed CCM orelectrolyte membrane 1085 as the individual GDLs 1066 a, 1066 b, 1076 a,1076 b and the electrolyte membrane 1085 pass between lamination rollers1081, 1082 to form a subgasketed 5-layer MEA web 1086. The subgasketed5-layer MEA web 1086 may be wound onto a roll or cut, e.g. by sheeterknife 1087 into individual 5-layer MEAs 1089.

The process control module 1099 illustrated in FIGS. 10A-10E includessensors and control electronics for controlling the relative speed andposition of fuel cell subassembly components to ensure proper alignmentbetween the various fuel cell subassembly layers. For example, theprocess control module 1099 may include one or more sensors that sensean edge of the membrane web 1085 to control the cross web position ofthe membrane web 1085. In some implementations, fiducials disposed onthe membrane web 1085 and/or aligned through cutouts in one or more ofthe layers of the membrane web may be sensed by sensors of the processcontrol module to control the down web position of the membrane webrelative to other fuel cell subassembly components. For example, sensedfiducials may be used to control the positioning of the first and secondindividual adhesive GDLs 1066, 1076 on the membrane web 1085.

Foamed vacuum die 1012 (see FIG. 10B) is used to cut the CCM orelectrolyte membrane web into individual CCMs or individual electrolytemembranes and is illustrated in more detail in the cross sectional viewof FIG. 13A and the exploded view of FIG. 13B. The foamed vacuum die1012 comprises a cylindrical core having a number of die cavities 1316and gaps 1315 between the die cavities 1316. Vacuum is applied in thedie cavities 1316 through holes 1311 in the core 1310. Inserts 1320 aredisposed within the die cavities. The inserts 1320 may be made of a foammaterial that facilitates application of vacuum both through thethickness of the material and laterally within the material. The vacuumapplied via the holes 1311 in the core 1310 and through the die cavityinserts 1320 retains the individual electrolyte membranes 1313 a, 1313b, 1313 c on the surface of the foamed vacuum die. The foam inserts 1320may include one or a number of porous layers. The material of the foaminserts 1320 is sufficiently compliant to protect the individualelectrolyte membranes 1313 a, 1313 b, 1313 c from damage during themanufacturing process.

The foamed vacuum die 1012 includes one or more blades 1312 that extendoutward from the surface of the core 1310 and just below the surface1321 of the foam insert 1320. The blades 1312 are configured to cut amembrane web 1323 (or other type of web) into individual membranes 1313a, 1313 b, 1313 c as the foamed vacuum die 1012 rotates around its axis.The foam inserts 1320 apply sufficient pressure to the individualmembranes 1313 a, 1313 b, 1313 c to allow adhesive attachment ofmembranes 1313 a, 1313 b, 1313 c to the subgasket web, while providingsufficient compressibility to avoid allowing the die blades 1312 toscore the subgasket web 1020 when attaching the membranes 1313 a, 1313b, 1313 c.

FIG. 13B illustrates the foamed vacuum die 1012 and a process forpreparing a foamed vacuum die. The vacuum die 1012 includes a rotatablecore 1310 with one or more die blades 1312 having a height of about0.057 inches extending outward from the surface of the rotatable core1310. The arrangement of the die blades 1312 defines die cavities 1316and gaps 1315 between the die cavities 1316. At least within the diecavities 1316, the rotatable core 1310 is perforated with holes 1311that extend through the outer surface 1319 of the rotatable core 1310 tofacilitate application of a vacuum to the outer surface 1319 of the core1310.

Multi-layer inserts 1320 are disposed within the die cavities 1316. Thegaps 1315 between the die cavities 1316 do not have the inserts. To formthe inserts 1320, initially a 3.5 mil PET tape layer 1351 is applied tothe outer surface 1319 of the core 1310 within the die cavity 1316,followed by a 0.050 inch foam with adhesive layer 1352 and a 6 miladhesive layer 1353. The 6 mil double stick adhesive layer 1353initially includes a release liner (not shown). After installation ofthe insert inner layers comprising the PET tape 1351, foam 1352, andadhesive layer 1353, holes 1361, 1362, 1363 are melted in each of theinsert inner layers 1351, 1352, 1353 to facilitate transfer vacuum tothe outer surface of the insert 1320. After removal of the releaseliner, an outer layer of porous breathable through-plane or in-planematerial 1354 is adhered to the foam 1352 via the adhesive 1353.

MEAs comprising electrolyte membranes with one sided adhesive subgasketsand two sided adhesive subgaskets were manufactured and temperaturetested. FIG. 14 illustrates a sample MEA construction having a two sidedadhesive subgasket prior to testing. The subgasket edge overlaps themembrane edge by approximately ⅛ inches.

FIG. 15 illustrates the MEA construction of FIG. 15 after temperaturetesting at 90 C. for 20 hours. During heat testing, the membrane becamedisplaced and can be seen protruding through the adhesive-adhesiveinterface between the two subgaskets. The gasket region of the MEA wascompressed to a hardstop for sealing purposes. The pressure in thegasket region combined with the temperature and the ability of theelectrolyte membrane to absorb water appeared to cause enoughlubrication for the membrane to slip and extrude beyond its intendedboundaries. This membrane extrusion beyond boundaries may or may notoccur depending on the gasket configuration, compression system, andpressure applied to the gasket region.

FIG. 16 illustrates an MEA construction that incorporates a one-sidedadhesive subgasket on the membrane. The subgasket overlaps the membraneedge by about ⅛ inch. In this construction, a first subgasket layerincludes an adhesive which bonds the first subgasket layer to the secondsubgasket layer which does not include adhesive.

FIG. 17 illustrates the MEA construction of FIG. 16 after temperaturetesting at 90 C. for 20 hours. After testing, the MEA using the onesided adhesive subgasket shows little or no extrusion of the membraneproviding a solution to the problem witnessed in FIG. 15.

The foregoing description of the various embodiments of the inventionhas been presented for the purposes of illustration and description. Itis not intended to be exhaustive or to limit the invention to theprecise form disclosed. Many modifications and variations are possiblein light of the above teaching. For example, the various rotary bondingprocesses described with reference to the accompanying figures caninstead be accomplished using non-rotary methods and apparatuses, suchas by use of step and repeat compression processes and apparatuses asare known in the art, for example. It is intended that the scope of theinvention be limited not by this detailed description, but rather by theclaims appended hereto.

1. A fuel cell roll good subassembly, comprising: a plurality ofindividual electrolyte membranes, each electrolyte membrane comprising acenter region; one or more first subgaskets attached to the individualelectrolyte membranes, each of the first subgaskets having at least oneaperture, the first subgaskets arranged so that the center regions ofthe individual electrolyte membranes are exposed through the aperturesof the first subgaskets; and a second subgasket comprising an web havinga plurality of apertures, the second subgasket web arranged so thatcenter regions of the individual electrolyte membranes are exposedthrough the apertures of the second subgasket web.
 2. The roll goodsubassembly of claim 1, wherein; each of the one or more firstsubgaskets comprises a first subgasket layer having a first subgasketsurface oriented toward the electrolyte membrane, the first subgaskethaving a first adhesive layer disposed on the first subgasket surface;and the second subgasket comprises a second subgasket layer having asecond subgasket surface oriented toward the electrolyte membrane,wherein a second adhesive layer is not disposed on substantial portionsof the second subgasket surface.
 3. The roll good subassembly of claim2, wherein the first adhesive layer of each of the first subgaskets isattached to the second subgasket surface.
 4. The roll good subassemblyof claim 1, wherein: each of the first subgaskets comprises a firstsubgasket layer having a first subgasket surface oriented toward theelectrolyte membrane, each of the first subgaskets having a firstadhesive layer disposed on the first subgasket surface; and the secondsubgasket comprises a second subgasket layer having a second subgasketsurface oriented toward the electrolyte membrane, the second subgaskethaving a second adhesive layer disposed on the second subgasket surface.5. The roll good subassembly of claim 1, wherein the one or more firstsubgaskets is one first subgasket comprising an web having a pluralityof apertures.
 6. The roll good assembly of claim 1, wherein at leastsome of the individual electrolyte membranes are catalyst coatedmembranes.
 7. The roll good assembly of claim 1, further comprising gasdiffusion layers or catalyst coated gas diffusion layers disposed overthe center regions of the individual electrolyte membranes.
 8. The rollgood subassembly of claim 1, wherein; each of the one or more firstsubgaskets comprises a first subgasket layer having a first subgasketsurface oriented toward an individual electrolyte membrane, each of theone or more first subgaskets having a first adhesive layer disposed onthe first subgasket surface; the second subgasket comprises a secondsubgasket layer having a second subgasket surface oriented toward theindividual electrolyte membranes, wherein a second adhesive layer is notdisposed on the second subgasket surface.
 9. A fuel cell roll goodsubassembly, comprising: a plurality of individual electrolytemembranes, each individual electrolyte membrane comprising a centerregion; and a subgasket web attached to the plurality of individualelectrolyte membranes, the subgasket web having a plurality of aperturesand arranged so that the center regions of the individual electrolytemembranes are exposed through the apertures of the subgasket web. 10.The fuel cell roll good assembly of claim 9, wherein the subgasket webcomprises a ladder web.
 11. A fuel cell subassembly, comprising: anelectrolyte membrane; and a first subgasket adhesively attached to theelectrolyte membrane, the first subgasket having a first subgasketsurface oriented toward the electrolyte membrane and a first adhesivelayer disposed on the first subgasket surface; and a second subgaskethaving a second subgasket surface oriented toward the electrolytemembrane, wherein the second subgasket does not include a secondadhesive layer on substantial portions of the second subgasket surface.12. The fuel cell subassembly of claim 11, wherein the second subgasketis devoid of adhesive on the second subgasket surface.
 13. The fuel cellsubassembly of claim 11, wherein the first adhesive layer is in contactwith the second gasket surface.
 14. The fuel cell subassembly of claim11, wherein the second subgasket is not adhesively attached to theelectrolyte membrane and is adhesively attached by the first adhesivelayer to the first subgasket.
 15. A fuel cell roll good subassembly,comprising: a plurality of individual electrolyte membranes, eachelectrolyte membrane comprising a center region; one or more firstsubgaskets adhesively attached to the individual electrolyte membranes,each of the first subgaskets having at least one aperture, the firstsubgaskets arranged so the center regions of the individual electrolytemembranes are exposed through the apertures of the first subgaskets; anda second subgasket comprising an web having a plurality of apertures,the second subgasket web arranged so that second surfaces of the centerregions of the individual electrolyte membranes are exposed through theapertures of the second subgasket web, wherein an adhesive layer is notdisposed on substantial portions of the second subgasket surface. 16.The fuel cell roll good subassembly of claim 15, wherein the firstadhesive layer of each of the first subgaskets is in contact with thesecond subgasket surface.
 17. The fuel cell roll good subassembly ofclaim 15, wherein the one or more one or more first subgaskets comprisesa web having a plurality of apertures.
 18. The fuel cell roll goodassembly of claim 15, wherein the electrolyte membrane comprises acatalyst coated membrane.
 19. The fuel cell roll good assembly of claim15, further comprising gas diffusion layers or catalyst coated gasdiffusion layers disposed over the center regions of the individualelectrolyte membranes.
 20. An automated roll to roll method of making afuel cell roll good subassembly, comprising: providing relative motionbetween an elongated first subgasket web having a plurality of aperturesand a plurality of individual electrolyte membranes, each individualelectrolyte membrane having a center region; aligning the individualelectrolyte membranes with the first subgasket web so that a centerregion of each electrolyte membrane is aligned with an aperture of thefirst subgasket web; and attaching the individual electrolyte membranesto the first subgasket web.
 21. The method of claim 20, wherein thefirst subgasket web is disposed on a repositionable adhesive carrierweb.
 22. The method of claim 20, further comprising: cutting the firstsubgasket web having the individual electrolyte membranes attachedthereto into a plurality of individual subgasketed membranes; providingrelative motion between a second subgasket web having a plurality ofapertures and the plurality of individual subgasketed membranes;aligning the individual subgasketed membranes with the second subgasketweb so that a center region of each electrolyte membrane is aligned withan aperture of the second subgasket web; and attaching the individualsubgasketed membranes to the second subgasket web.
 23. The method ofclaim 22, wherein the second subgasket web is disposed on repositionableadhesive carrier web.
 24. The method of claim 22, wherein: the firstsubgasket web includes a first subgasket surface oriented toward theindividual electrolyte membranes and a first adhesive layer is disposedon a first subgasket surface; and the second subgasket web includes asecond subgasket surface oriented toward the individual electrolytemembranes and a substantial portion of the second subgasket surface doesnot include a second adhesive layer.
 25. The method of claim 22,wherein: the first subgasket web includes a first subgasket surfaceoriented toward the individual electrolyte membranes and a firstadhesive layer is disposed on a first subgasket surface; and the secondsubgasket web includes a second subgasket surface oriented toward theindividual electrolyte membranes the second subgasket surface does notinclude a second adhesive layer.
 26. The method of claim 20, furthercomprising: providing relative motion between an second subgasket webhaving a plurality of apertures and the first subgasket web having theindividual electrolyte membranes attached thereto; aligning the secondsubgasket web with the first subgasket web having the individualelectrolyte membranes attached thereto so that a center region of eachelectrolyte membrane is aligned with an aperture of the second subgasketweb; and attaching the first subgasket web having the individualelectrolyte membranes attached thereto to the second subgasket web. 27.The method of claim 26, wherein: the first subgasket web includes afirst subgasket surface oriented toward the individual electrolytemembranes and a first adhesive layer is disposed on a first subgasketsurface; and the second subgasket web includes a second subgasketsurface oriented toward the individual electrolyte membranes and thesecond subgasket surface does not include a second adhesive layer. 28.The method of claim 26, wherein one or both of the first subgasket weband the second subgasket web are disposed on a repositionable carrierweb.
 29. The process of claim 20, further comprising: moving anelectrolyte membrane web into contact with a rotating die; and cuttingthe electrolyte membrane web into the individual electrolyte membranesusing the rotating die.
 30. The process of claim 29, wherein therotating die comprises a rotating vacuum die that retains the individualelectrolyte membranes on a surface of the rotating die and moves theindividual electrolyte membranes into contact with the first subgasketweb.
 31. The method of claim 30, wherein the rotating die comprises: acylindrical core; die blades on the cylindrical core defining diecavities and gaps between the die cavities; and compliant die cavityinserts disposed within the die cavities.